Fork lift truck



H. R. ROGANT FORK LIFT TRUCK April 3, 1962 2 Sheets-Sheet 1 Original Filed Jan. 26, 1959 uvmvrok. Humbert R R W a wavadw ATTORNEYS H. R. RQG'ANT FORK LIFT TRUCK April 3, 1962 2 Sheets-Sheet 2 Original Filed Jan. 26, 1959 INVENTOR. H MHZ Rgqomt 7 aw o a M ATTORNEYS United States Patent 3,027,961 FORK LIFT TRUCK Humbert R. Rogant, Wiiloughhy, flhio, assignor to James Campbell Smith, Inc., Willoughhy, Elite, :1 corporation of 01min Original application Jan. 26, 1959, Ser. No. 788,928, now Patent No. 2,959,425, dated Nov. 8, 1969. Divided and this application lune 2.0, 196d, Ser. No. 37,384 3 Claims. (Q1. led-77) This invention relates to fork lift trucks and more particularly it pertains to such trucks equipped with a battery-powered motor and hydraulic actuating means, and this application is a division of my copending application, Serial No. 788,928, filed January 26, 1959, now Patent No. 2,959,425, issued Novemebr 8, 1960.

Fork lift trucks have been widely accepted by industry for expediting the movement of materials within a plant. The trucks usually include a pair of load-carrying arms or lifting forks, a fork elevator which is mounted on a wheel-mounted housing which includes the prime mover, and control and steering parts at the operators position. Although most fork lift trucks have been maneuverable, there has been a continued effort to increase maneuverability, particularly in congested areas.

One way to increase maneuverability is to reduce the size of the truck housing including the chassis as much as possible to achieve greater compactness without sacrificing the minimum structure necessary to handle heavy loads. In an effort to reduce the size of the truck housing many prior fork lift truck constructions have sacrificed another requisite of fork lift trucks, namely the accessibility of operating parts for easy repair and maintenance.

Still another problem in achieving greater maneuverability of fork lift trucks has been the provision of more adequate steering mechanism. Some fork lift truck constructions are provided with steering mechanisms which give substantial maneuverability. However, the mechanism is complicated, cumbersome, and difiicult to repair and maintain.

The device of the present invention provides a fork lift truck which is compact in construction and therefore highly maneuverable in small congested areas. At the same time, the truck includes operating parts which are readily accessible and are not located in out-of-the- Way places which make for higher production costs due to increased downtime and delays in operation of the motorized truck.

Accordingly, it is a general object of this invention to provide a fork lift truck which is highly maneuverable.

It is another object of this invention to provide a fork lift truck which is compact in construction without sacrificing accessibility to vital operating parts.

It is another object of this invention to provide a fork lift truck having a hood or access cover on which electrical and hydraulic controls are provided on the underside of the hood or access cover which when opened brings the controls into quick access.

Finally, it is an object of the present invention to provide an improved fork lift truck construction by which the described problems and difficulties are overcome and the foregoing objects and desiderata are obtained in a simple, effective and inexpensive manner without creating maintenance, repair and adjustment problems in maintaining efiiciency.

These and other objects apparent to those skilled in the art from the following description and claims may be obtained, the stated results achieved, and the described diificulties overcome by the discoveries, principles, apparatus, parts, elements, combinations and subcombinations which comprise the present invention, a preferred embodiment of which-illustrative of the best mode in which applicant has contemplated applying the principles-is set forth in the following description and shown in the drawings, and which is particularly and distinctly pointed out and set forth in the appended claims forming part hereof.

The nature of the improvements in the fork lift truck construction of the present invention may be stated in general terms as including a body housing having walls forming a compartment containing prime mover means for the truck, the body also having an operators platform adjacent the compartment, a hood or access cover for the compartment movable between closed and open positions, some parts associated with the prime mover means mounted on the inner surface of the hood, truck control means including a steering wheel mounted on a steering column having an offset portion for rotating the steering wheel between operative and non-operative positions, the operative position of the steering wheel extending through the path of opening the compartment hood, a turning wheel mounting the truck body, and means operatively connecting the steering wheel to the turning wheel.

In the drawings which are illustrative of the preferred embodiment of the invention, by way of example, and in which similar numerals refer to similar parts thereof:

FIGURE 1 is a perspective view of a fork lift truck showing the steering wheel disposed in operating position over one end of the hood of the truck housing;

'FIG. 2 is a fragmentary elevational view showing the steering wheel in the non-operating position to provide clearance for opening of the hood;

FIG. 3 is a horizontal sectional view taken on the line 3-3 of FIG. 2, showing chain reduction gear means for the steering Wheel;

FIG. 4 is a rear end view of the truck taken partly in section to show the steering mechanism and dual rear wheel;

FIG. 5 is a perspective view showing the mounting for the dual rear wheel and connection with the steering column; and

FIG. 6 is a fragmentary perspective view showing the hood in the open position with electric and hydraulic control parts mounted on the undersurface thereof.

In FIG. 1 a fork lift truck is generally indicated at 1. It includes a truck body or housing 2 and a fork elevator 3 with a pair of load-carrying arms or lifting forks 4 movable up and down the fork elevator by hydraulic cylinder means 3a.

The truck body 2 is mounted on a pair of forward drive wheel 5 and dual steer or turning wheels 6 (FIG. 4). The dual steer wheels include turning means generally indicated at 7. In addition, the truck body includes an operators platform 8 having a foot pedal 9 extending therefrom. Control means for maneuvering the truck are generally indicated at :10 and include a steering wheel 11 and a number of levers 12, all of which are conveniently located above and forwardly of the platform 8 at the top of the truck body.

The truck body also includes a hood or access cover 13 which is horizontally disposed in the closed position as shown in FIG. 1 and which is mounted on a hinge 14 for raising the hood to the open position as shown in FIG. 6.

The steering wheel 11 is a part of a turning mechanism which includes the turning means 7, a steering shaft 15 extending through a tubular steering column 16, a reduction gear means generally indicated at 17 (FIG. 3) within a reduction gear housing 18 at the upper ends of the shaft 15 and column 16, and a steering wheel shaft 19 at the top of which the steering wheel is mounted.

As shown in the several views of the drawing, the upper end of the turning mechanism is offset from the lower portion by a distance equal to the distance between the shafts and 19 so that during normal operation of the truck 1 the upper end of the turning mechanism,

namely the steering wheel 11 and steering wheel shaft 19, are forward of the steering shaft and column 15 and 16. In the forward position the steering wheel 1-1 is disposed over a portion of the hood or access cover 13 and is within convenient reach of the operator.

When it is necessary to raise the hood for access to the operating parts within the truck housing 2, the steering wheel 11 is turned about the steering shaft 15 to a position where it no longer extends over the hood 13 as shown in FIGS. 2 and 6. During operation of the truck 1 the steering wheel 11 is maintained in its operative position over :the hood 13 by a locking pin having a handle 21 which pin is insertable into an aperture 22 in the housing 2. The pin 2b is threadedly engaged in a flange or plate 23 extending from the reduction gear housing 18.

The reduction gear means 17 as shown in FIG. 3 includes a sprocket 24 mounted at the lower end of the steering wheel shaft 19, a sprocket 25 mounted at the uper end of the steering shaft 15, and a continuous sprocket chain 26 extending over and around the sprockets. The shaft 19 is journalled in upper and lower portions of the reduction gear housing 18 in a conventional manner. Likewise, the steering shaft 15 is journatlled at 27 and 28 within the steering column in a conventional manner.

At the lower end of the steering column 1.5 a pinion 29 is mounted for engagement with a ring gear 3i that is peripherally disposed about a rotating plate 31 as shown in FIGS. 4 and 5. At opposite sides of the plate 31 a pair of brackets 32 is provided for mounting of the dual steer wheels 6 on an axle 33 extending between the brackets.

In addition to the foregoing, the turning means includes a bogey wheel 34 which is rotatably mounted on a shaft 35 extending centrally upwardly from the rotating plate 31 through a shaft-receiving aperture (not shown) in an underplate 36 of the housing 2. The shaft 35 is retained in place by a nut 37 engaging the threaded upper portion of the shaft. A plurality of rollers 38 are mounted on indi't' idual roller shafts 39 extending radially outwardly from the periphery of the bogey wheel 34. The rollers 33 operate between the underplate 36 and the rotating plate 31 to facilitate steering of the truck 1 and the bogey wheel 34 absorbs shock. in operation, the steering wheel 11 functions through the steering shafts 15 and 19, the reduction gear means 17, and the turning means 7 to turn the dual steer wheels 6.

As shown more particularly in FIG. 6, the truck body or housing 2 includes oppositely disposed side plates 4% and ll, a back plate 42, a front plate 43, the underplate 36 which, as shown in FIG. 4, is mounted between chassis members 4-4 and 45, and the hood or access cover 13.

The plates 46-43 and hood 13 provide a compartment 46 within which battery means 47 are provided together with other operating members such as a motor for propelling the truck and hydraulic flow means including pump 55 for operating the cylinder 3a. For opening and closing of the hood 13, the hood back edge has a recess 43 to provide clearance for the upper end of the steering column 16 and journal 27. The undersurface of the hood 13 is provided with electrical controls such as relays and switches diagrammatically indicated at 49 and 59, connected by cable 57 to the motor 55 as well as bydraulic controls such as valves diagrammatically indicated at 51, and hydraulic hoses 52 connecting the valves 51 to the hydraulic flow means including the pump 56.

In addition, connecting rods 53 extend between the hydraulic valves 51 and the lower ends of two of the levers 12. Another connecting rod 54 extends from the lower end of a third lever 12 to the electric switch 59. Thus the several electrical and hydraulic controls 49 to 54 are conveniently disposed on the undersurface of the hood l3 where they are available for ready access when the hood is lifted to the open position as shown in FIG. 6.

Accordingly, the present invention provides an improved fork lift truck construction which avoids prior art difficulties and obtains described results by providing a compact maneuverable fork lift truck having a steering wheel and associated turning mechanism which are directly interconnected. In addition the fork lift truck includes readily accessible electric and hydraulic control means which are mounted on the undersurfaoe of the hood or access cover of the housing of the truck for quick and easy maintenance and repair.

In the foregoing description, certain terms have been used for brevity, clearness and understanding, but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such terms are utilized for descriptive purposes herein and not for the purpose of limitation and are intended to be broadly construed.

Moreover, the description of the improvements is by way of example and the scope of the present invention is not limited to the exact details illustrated, or to the specific mechanisms shown.

Having now described the features, discoveries and principles of the invention, the construction, operation and use of the improved mechanism and the advantageous, new and useful results obtained thereby; the new and useful parts, elements, constructions, mechanisms, combinations, subcombinations, and arrangements, and mechanical equivalents obvious to those skilled in the art, are set forth in the appended claims.

I claim:

1. In a truck of the class described, a compartment containing a motor and hydraulic flow means, a cover for said compartment movable into and out of covering position, control members mounted upon the inner surface of the cover, flexible means connecting said control members to the motor and the hydraulic flow means, manually operated levers, means mounting said levers on the cover for movement relatively to the cover and for movement bodily with the cover when the cover is removed from covering position relatively to the compartment, and means operativeiy connecting said levers to said con,- trol members in all positions of the cover, whereby in all positions of the cover operation of said levers will operate said control members to control the motor and hydraulic flow means.

2. In a truck of the class described, a compartment containing a motor and hydraulic flow means, a cover for said compartment movable into and out, of covering position, a switch and relay means mounted upon the inner surface of the cover, flexible cable means connecting said switch and relay means to the motor, valve means mounted upon the inner surface of the cover, flexible hose means connecting said valve means to the hydraulic flow means, manually operated levers, means mounting said levers on the cover for movement relatively to the cover and for movement bodily with the cover when the cover is removed from covering position relatively to the compartment, and means operatively connecting said levers to the switch and relay means and the valve means in all positions of the cover, whereby in all positions of the cover operation of said levers will operate said switch and relay means, and said valve means to control the motor and hydraulic flow means.

3. In a truck of the class described, a compartment containing a motor and hydraulic flow means, a cover for said compartment movable into and out of covering position, a switch and relay mounted upon the inner surface of the cover, a flexible cable connecting said switch and relay to the motor, a valve mounted upon the inner surface of the cover, flexible hose connecting said valve to the hydraulic flow means, a manually operated lever, means mounting said lever on the cover for movement relatively to the cover and for movement bodily with the cover when the cover is removed from covering position relatively to the compartment, means operatively connecting said lever to said switch and relay in all positions of the cover, a second manually operated lever, means mounting said second lever on the cover for movement relatively to the cover and for movement bodily with the cover when the cover is removed from covering position relatively to the compartment, and mean operatively connecting said second lever to said valve in all positions of the cover, whereby in all positions of the cover operation of said first-named lever will operate said 6 switch and relay to control the motor, and operation of said second lever will operate said valve to control the hydraulic flow means.

References Cited in the file of this patent UNITED STATES PATENTS 2,605,008 Schroeder July 29, 1952 2,833,365 Kesl May 6, 1958 2,876,857 Beyerstedt Mar. 10, 1959 2,885,016 Ayers May 5, 1959 2,899,093 Morrell Aug. 11, 1959 

